Avoid modulo 0
Avoid modulo 0

Coverity pointed out that 'size' might be 0 (even if the 'find()' would
detect this). This commit fixes this and avoids entering 'find()' at
all.

naimdjon/fluxbox,naimdjon/fluxbox,lukoko/fluxbox,luebking/fluxbox,Arkq/fluxbox,Arkq/fluxbox,lukoko/fluxbox,olivergondza/fluxbox,Arkq/fluxbox,luebking/fluxbox,lukoko/fluxbox,naimdjon/fluxbox,olivergondza/fluxbox,Arkq/fluxbox,olivergondza/fluxbox,Arkq/fluxbox,olivergondza/fluxbox,lukoko/fluxbox,luebking/fluxbox,luebking/fluxbox,luebking/fluxbox,naimdjon/fluxbox,naimdjon/fluxbox,lukoko/fluxbox,olivergondza/fluxbox